Dredge pump



J. W. STAUP Sept. 20, I932.

DREDGE PUMP Filed May 9, 1930 gmwwtoo IOH N Wm u p,

1 axial section wearing plate. I

The pump casing inwhich my invention UNITED, STATES T NT-orFica JOHN W. STAIIY, OF TERRE .HAUTE INID IANA DREDGE PUMP Application fil ed Ma s, 19:20. Serial No. 450,909.

My invention is concerned with centrifugal pumps, particularly with pumps of the type having an axially adjustable wearing plate which can be maintained in proper relation to the pump-impeller.

invention to produce such a pump in which by-passing of the .pumped liquidback of the" wearing plate will be prevented.

In carrying out my nvention, I provide within the pump-casing, and desirably on; each side of the impeller, a wearing'plate mounted for axial adjustment; and I provide I each wearing plate and the adj acent end-wall of the pump casing with engaging cylindri-' 3 cal surfaces each pair of which forms a seal preventing any radial flow of liquid between the wearing plate and such end-wall.

The accompany ng drawingillustrates a pump embodying my invention: Fig.1 is an impeller; Fig. 2 is an elevation of one endplate of the pump-casing; and Fig. 3 is an elevation showing the exterior surface of a may be embodied is susceptible of consider,- able modification, that shown in the drawing comprising an annular body 10 'andendplates 11 and 12 which are mounted on opposite sides of the body 10 as by means. of bolts 13. One of the end-plates, hereshown as theend-plate'll, is provided with an inlet opening 1 and the otherend-plate is provided with a bearing for an impeller shaft 15 which projects into the interior of the casing and has mounted upon it an impeller 16.

The construction and operation of such a pump, in general, is well understood. As the impeller is rotated, liquid is drawn in through the inlet opening into the impeller 16. Such liquid escapes from the impeller under the action of centrifugal force to the outer portion of the casing from which it 1s discharged through a suitable outlet opening (not shown) p .In such a pump, it is desirable that the axial end faces of the impeller be closely adjacent to stationary surfaces which may be the inner surfaces of wearingfplates. These surfaces, and the axial end-faces of the im- It is the object of my hrough the pump-casing and peller, are susceptible to wear, particularly y when the pump is employed to pump liquids containing 'sand or other abrasive material. To compensate'for the wear thus produced, it has been proposed to make the wearing plates axially adjustable from without the casing in order that a proper fitbetween the impeller and the gwearing plate may be maintained at, .alltimes. Q 1' f H In the pump shown in the drawing, there are'two wearing plates 17 and'18 associated IGSPQC GIVGlY" with the end plates 11 andv 12. Associated with each wearing plate are a series of adjusting screws 20 and a series of adjusting bolts 21. The former-are screwthreadedly received in nuts20" located-in noncircular recesses in the inner faces of the end- This adjusting means, while permitting any v desired adjustment of the wearing jplates,

still holds each wearing plate positively in any position of adjustment.

For the purpose of preventing flow of liquid between theend plates andthe wearing I plates, I provide,as previously stated, cylindricalsurfaces on thewearing plates I and end plates, which surfaces respectively 'en-.

gage to provide a multiplicity of seals. As.

shown in the drawing, the periphery ofeach end plate fits closely the bore of the ca-sing-body 1 0 to provide one p-airof sealing surfaces. In addition, eachwearing plate is provided at its periphery with an outwardly extending annular flange 25 whic'h is re- .ceived withina rabbet groove in the adjacent wearingplate. j The in ner surfaces of this flange and theengaging inner surface-of the rabbet groove provide another seal. A similar annular flange or shoulder 26 near the inner end of each wearing plate is re ceived in an associated rabbet groove in the adjacent end-plate to provide an additional seal. Further, between the center and exterior of each wearing plate, there may be one or more additional annular flanges 28 which are received in annular grooves in the associated end plate. Each of these intermediate flanges with its associated groove provides two sets of sealing surfaces.

If desired, one of the flanges 28 may be provided with a seriesof'undercut slots 28 for the reception of the heads of the bolts 21. I i 1 While I have shown all the flanges as being on the wearing plates and all the flangereceiving grooves as being on the end plates, it will be apparent that this arrangement,

infany or all instances, can be reversed if desired.

The sealing surfaces should be cylindrical so that axial adjustment of the wearing plate will not interfere with their interengages ment. The seals provided by the sealing surfaces prevent any liquid from flowing from the periphery of the casing-body 10 toward the center of the pump between the wearing plates and the end-plates, If such flow. of liquid were permitted, it would find its way again into the impeller to be re-pumped, and this would represent a substantial loss in efficiency. Further, where the liquid being pumped carries abrasive material, any flow back of the wearing plates'would seriously abrade the adjustingmeans.

I claim as my invention: i I j 1. In a centrifugal pump having an impeller and a casing provided with end-walls between which the impeller rotates, a wearing plate between said impellerand one of said end-walls, means for adjusting said wearing plate toward or away from said impellenprovisions associated with said wearing plate and. its associated wall for preventing radial flow of liquid between such end-wall and wearing plate comprising an annular flange on oneo-f said parts and an annular flange-receiving groove on the other part, theaxially extending sides of such flange and groove being concentric cylindrical surfaces, the cylindrical surfaces of said flange cooperating with those of said of liquid between such end-walland wearing plate. 7 V

' 2. In a centrifugal pump having an impeller and a casing provided with end-walls between which the impeller .rotates, a wearing plate between said impeller and one of said end-walls, means .for adjusting said wearing plate toward or away from said 1mpeller, provisions associated with said wearing plate and its associated wall for preventing radial flow of liquid between such endwall, and wearing plate comprising an annular flange on said wearing plate and an between which the impeller rotates, a wearing plate between said impeller and one of said end walls, an annular rabbet groove in said end wall having cylindrical side surfaces, a complementary annular flange on said wearing plate. having cylindrical surfaces mating with. the side surfaces of said groove and having a series of undercut slots, bolts extending through said end wall into said groove and havingtheir heads received in said undercut slots, nuts on said bolts outside said end wall whereby said wearing plate may be drawn toward said end wall, and

thrust screws in said end walls whereby said wearing plates may be pushed toward said impeller.

4. In av centrifugal pump having an impeller and a casing provided with end walls between which the impeller rotates, a Wearing plate between saidim'peller and one of said end walls, a plurality of. annular rabbet grooves in said end wall having cylindrical side surfaces, complementary annular flanges on said wearing plate, having cylindrical surfaces mating with the side sur-, faces ofsaid grooves, one ofsaid flanges having a series of undercut slots, bolts extending through said .end wall into the groove associated with the flange having said undercut slots and having their heads received in said undercut, nuts'on said bolts outside said end wall whereby said wearing plate may be drawn toward said end wall, and thrust screws in said end walls whereby said wearing plates may be pushed toward said impeller.

my hand at Terre Haute, Indiana, this 6th day of May, A. D. one thousand nine hun- I In, witness. whereof, I have hereunto 'set' 

